The basin of the river Chopim bes situated in the southwestern part of the state of the Paran, between the parallels 2530? 2640? of South latitude and meridians 5130? 5320? of longitude West. This basin possesss a length of 147Km and an area of draining of 7500Km2 basically develops in the direction the Southeast-northwest. (CLOSE-WOVEN PART OF A FISHING NET, 2001, p.42) In accordance with the Close-woven part of a fishing net (2001, p.42) the river Chopim and its tributaries are placed entirely on the Basin Sedimentary of the Paran. Its estuary is located approximately the 290 km of the confluence of the river Iguau with river Paran, in the reservoir of the Plant Hydroelectric plant 10 Caxias Jump and about km downstream of the barrage of Osrio Jump. The springs of the river Chopim are located in the 1,200 altitudes that surpass m. The total extension of the main course of the river is of the order of 450 km. Of the spring of the river around km 209 the inclination of the stream bed even is of approximately 2,9 m/km, and since this point until the estuary the inclination is approximately 1.1 m/km.

The river Chopim runs on basaltos and similar rocks, showing a simple geomorfologia. Extremely rich in rapids and waterfalls, it presents a succession of fast jumps and a sinuosa conformation, full of returns and elbows, always if keeping inside of a valley. In accordance with the Close-woven part of a fishing net (2001, p.43), the main uses of the water of the basin of the River Chopin are public supplying, piscicultura and industrial supplying Is observed that the use of the water for public supplying corresponds 53.9% of the consumed daily volume granted in the basin, followed of the use for piscicultura. The too much existing uses (agriculture, cattle, commerce) represent less than 0,1% of the daily volume of water granted.